基于Hoek-Brown屈服准则的隧道围岩稳定性分析

Stability analysis of tunnel surrounding rock based on Hoek-Brown yield criterion

基于隧道稳定性分析时常常采用Mohr-Coulomb屈服准则,但岩石屈服时服从Hoek-Brown半经验公式屈服准则。在Hoek-Brown屈服准则中引入强度折减法用以研究隧道围岩的整体稳定性,且与基于等效的Mohr-Coulomb屈服准则的强度折减法进行比较。分析结果表明:在不同屈服准则条件下的整体稳定系数、围岩变形特点及潜在破坏面位置大体上是一致的,但也存在一定差异;所得围岩稳定范围可以为锚固支护提供合理的参数以及开挖前的地层加固提供参考。

Based on a semi - empirical rule for estimating shear strength of integral rock or joint rock masses, the Hoek - Brown yield criterion has been widely applied in analysis of the slope limit equilibrium, but rarely used in numerical simulation calculation of tunnel. In order to research the global stability of tunnel surrounding rock the strength reduction method was introduced into the Hoek- Brown yield criterion, and compared with the traditional strength reduction method which is based on the Mohr - Coulomb yield criterion. The factor of local stability was defined, the safety range of the rock masses stability were developed by the factor of local stability. The results show that the integral stability coefficient, the deformation characteristics of surrounding rock and the position of the potential failure surface under different failure criteria are roughly consistent, but there are still some differences among them. The rock masses stability can provide reasonable supporting parameter for the anchorage support, and give reference for the ground consolidation before excavation.